Leanne Hainsby

Leanne Hainsby married her Peloton colleague Ben Alldis in 2019. Alldis supported her during her breast cancer treatment, drawing on his own experience with skin cancer when he was 25.

Her mother and Alldis helped advocate for her during appointments and treatment, particularly when she felt too anxious or overwhelmed to speak with doctors herself.

Hainsby began dancing at the age of three and pursued a professional career before moving into fitness instruction. She worked as a backup dancer on stage with Taylor Swift, Kylie Minogue and Katy Perry.

Her move to Peloton followed a fitness class she taught at a boutique studio in London. Peloton instructor Cody Rigsby attended the class and encouraged her to meet with the company, while Robin Arzón later invited her to New York to audition. Hainsby accepted the opportunity in 2018, ending her professional dancing career.

She became Peloton’s first female UK-based instructor, teaching live from the company’s London studio. Her classes combine cycling with music, movement and encouragement to push beyond familiar limits.

Hainsby found a lump in her left breast in July 2022. After an initial assessment suggested it could be a hormonal cyst, she pursued further examinations, including an ultrasound, mammogram, biopsy, PET scan, CT scan and MRI. She was diagnosed with early triple-positive breast cancer, an aggressive form that was found to be treatable.

Her treatment began with in vitro fertilization to preserve her fertility. She then underwent 12 weeks of weekly chemotherapy, followed by a lumpectomy and lymph-node dissection on January 11, 2023, and two weeks of radiotherapy. Her maintenance treatment included tamoxifen, Herceptin and Zoladex.

Hainsby continued filming Peloton classes through much of her treatment because the routine helped her feel like herself. Chemotherapy caused her to lose around half of her hair, as well as her eyebrows and eyelashes. She later shared her experience publicly, encouraging people who feel dismissed by a doctor to seek a second opinion and trust their intuition.

Hainsby has described movement as the foundation of her life and said that staying connected to her body helped her through treatment. She does not regard the Peloton classes she teaches as her own workout, instead training with a personal trainer three times a week, primarily through strength sessions.

She has also spoken about the emotional challenges that continue after chemotherapy, surgery and radiotherapy. Her routine includes weekly therapy, phone-free morning walks with her dog Jags, and time in an infrared sauna at home. She has said that ongoing medication, injections and follow-up scans can remain a significant part of recovery even after the main treatment has ended.